Bill Reminder Notifications

[lynnsamuelson]

Implement email or in-app notifications for upcoming bills (3 days before due)

[alexcurnow]

First pass can just be a client-side notification icon in the nav menu coupled with highlighting, in some way, the bill itself on the bills & goals page. This will require the nav menu component to be aware of bills (fetch bills to check today's date against the bill's due date and decide whether to render the notification dot/icon/whatev).